Blur Student Names in Google Meet Recording

This article is written for tech-savvy professionals. The method is generic to redact all participant name in the recordings for businesses as well, not just student names as you see in the title.

Problem

Google Meet supports video recording that is saved to the meeting organizer's My Drive > Meet Recordings folder. The video only includes the active speaker and anything that is presented. As we tested, the video resolution is 720p or 1280x720.

Due to privacy concerns or legal compliance, some organizations do not want the speaker's name to be appear in the videos. For schools, students' identities should be protected to abide by student privacy laws such as COPPA. Google Meet has no such control for the organizer to remove the names from the video.

Solution

While it's impossible to control the source, we can do a post video processing on the recording to address the problem, by blurring the names in the video. We use the popular open source video processing tool FFmpeg for this job.

Instructions

1. First, you need a desktop environment, running Windows or macOS. Chromebooks are not supported. You have Google Drive for desktop installed so that the videos are synced to the device.
2. Download FFmpeg. It depends on your platform. We use the officially guided BtnN's ffmpeg-n4.4-80-gbf87bdd3f6-win64-gpl-4.4.zip build.
3. On windows, unzip the build and copy the bin/ffmpeg.exe file.
   
4. Go to your video folder. Paste the ffmpeg.exe file there.
5. Hold Shift and right click to pop the context menu. Select Open PowerShell window here.
   
6. In the opened PowerShell window, type the following command. Replace the THE_VIDEO_FILE_NAME and THE_OUTPOUT_VIDEO_FILE_NAME with your case.
   ./ffmpeg -i "THE_VIDEO_FILE_NAME" -filter_complex "[0:v] crop=150:20:965:432,boxblur=5 [fg]; [0:v] crop=150:25:10:683,boxblur=5 [fg2]; [0:v][fg]overlay=965:432[v2];[v2][fg2]overlay=10:683[v]" -map "[v]" -map 0:a -c:v libx264 -c:a copy -movflags +faststart "THE_OUTPUT_VIDEO_FILE_NAME"
   For example, if the file name is efe-qwrp-ofo (2021-08-04 at 13 45 GMP-7), then type
   ./ffmpeg -i "efe-qwrp-ofo (2021-08-04 at 13 45 GMT-7)" -filter_complex "[0:v] crop=150:20:965:432,boxblur=5 [fg]; [0:v] crop=150:25:10:683,boxblur=5 [fg2]; [0:v][fg]overlay=965:432[v2]; [v2][fg2]overlay=10:683[v]" -map "[v]" -map 0:a -c:v libx264 -c:a copy -movflags +faststart "efe-qwrp-ofo (2021-08-04 at 13 45 GMT-7) processed.mp4"
   
7. The command will then process your video and generates a new video in the same folder. You will find the differences as below between two videos.

What's the change?

The recording video only has 2 layouts, the full screen speaker layout and the side-by-side presentation and speaker layout. The participant names on the bottom left corner of their video block are blurred for both layouts. See the snapshots below.

If you'd like to remove participant names in live Google Meet sessions, please check out this article Hide Participants in Google Meet.